Method of preventing efflorescence on the surface of colored roofing granules



Patented May 25, 1937 UNITED STATES PATENT oFnce METHOD 0 ON THE GRANULES Paul Teeto N 0 Drawing. Application ficially coloring the same.

t of the invention is the provi- Another objec sion of a new and improve color pigment to the surfaces of ules.

' Other and the invention ceeds.

by fusing the the use of binder same thereon. The present invention rel In ates to r, Castleton, Commercial Company,

F PREVENTING 'EFFLORESCENCE SURFACE or COLORED ROOFING.

Vt, assignor to Central a corporation of Illinois December 4, 1934 Serial No. 756,006

8 Claims.

g granules subsequent to artid binder for securing roofing granadvantages of will appear as the description prothe latter type.

other materials as a color pigment to the ng. It would appear that the eflioresced material is not a Sul phate. In fact, t

he major portion of the bloom appears to be calcium carbonate.

20 granules used, the following found to give satisfactory rehaving a slate and a quartz formulas have been suits for granules With reference No. 1, varying amounts of frit and frits of difierent composiadditional fluxing agents.

It has been found that the amount of barium 50 for preventing which is sometimes found in and forms part of the frit is of no value in preventing the bloom or efflorescence. After the material has been added to the granules and thoroughly stirred, the same is subjected to heat to fuse the compos1tion onto the surface of the granules.

the granules are agitated to prevent agglomera- While the invention is disclosed more or less in detail, it is understood that the formulas enumerway of example only,. and that changes in their proportions may be made without departing from the spirit and scope of the appended claims.

I claim as my invention:-

1. A method of preventing subsequent efllorescence on the surface of slate granules which consists in mixing barium carbonate with the color pigment and an igneous binder and then fusing the binder on the granules.

2. A method of treating granules suitable for use on roofing material which comprises mixing barium carbonate, color pigment and a binder containing frit, mixing the mass with granules, fusing the binder on the granules and agitating the mass to prevent agglomeration.

3. A method of coloring roofing granules and subsequent efllorescence on the surface of the colored granules which comprises mixing a color pigment with an igneous binder containing frit of the lead base type and barium carbonate, then fusing the binder on the granules and agitating the mass to prevent agglomeration of the granules after the binder is fused.

4. A binder for attaching color pigments to the surface of granules having a slate base which comprises the following:-

Pounds rit 20-60 Sodium silicate -60 Barium carbonate -20 During the operation, or as long as necessary during the operation,

5. A binder for attaching color pigments to the surface of granules having a quartz base which preventing blooming on the surface of said roofing.

PAUL TEETOR.

comprises the following:-

Pounds Borax -30 5 Whiting 1-10 Barium carbonate 5-20 Sodium nitrate 0-5 Soda ash 2-10 China clay 0-5 10 Cobalt oxide 0-0.5 Feldspar 0-10 6. A granule having color pigment secured to the surface thereof by a binder fused thereon, said binder comprising:

Pounds Frit -60 Sodium silicate 0-60 Barium, carbonate 5-20 for each ton of granules. 7. A granule having color pigment secured to the surface thereof by a binder fused thereon, said binder comprising:

Pounds Borax 10-30 Whiting 1-10 Barium carbonate 5-20 Sodium nitrate 0-5 Soda ash 2-10 China clay 0-5 Cobalt oxide 0-0.5 Feldspar 0-10 for each ton of granules. 3' 0 8. Composition roofing comprising roofing material covered on one side by granules each of which has color pigment attached thereto by a frit binder and barium carbonate fused on the surface of the granules, said barium carbonate 40 

